The present invention is directed to a method and apparatus for manufacturing optical cables containing at least two light waveguides, which method and apparatus utilizes an extruder to which the light waveguides are supplied, and which serves the purpose of producing a protective sheath for the waveguide.
U.S. Pat. No. 4,414,165, whose disclosure is incorporated herein by reference thereto, and German Letters Patent 31 11 963, each disclose a method and apparatus for forming an optical transmission element having a fiber received in a tubular jacket containing filling material. Preferably, the jacket is formed by two concentric envelopes. As disclosed, one always proceeds so that the light waveguide is first manufactured and then is stored as an intermediate product, for example on a plate or a drum. The cable core is then composed of a plurality of these intermediate products on the basis of a separate stranding process that occurs at a different location and at a different time. The stranding itself can occur in a long lay or with changing stranding directions to form an SZ-stranding. Winding the intermediate product onto a drum or depositing the intermediate product represents an additional work outlay or cost and also requires storage in respective deposit areas.
German Patent 25 23 738 discloses a cable wherein the light waveguides are accommodated in interspaces or chambers of a core element that has the approximate cross sectional shape of a wheel having spokes. A tensile central element is provided in the middle and the overall structure is manufactured in one working cycle as a closed single-piece element. The disadvantage of such a structure is that the fiber of fiber bundles are placed into a closed structure and no protection is provided for these bundles or fibers, such as sleeves, without additional cost.